Andeew dekrom



UNITED STATES PATENT OFFICE.

ANDREW DERRoM, OF 'PATERSON, NEW JERSEY.

COMPOSITION MASTIC FOR COVERING ROOFS, TELEGRAPH-WIRES, AND THE LIKE.

SPECIFICATION forming part of Letters Patent No. 307,184, dated October 28, 1.884.

Application filed April 15, 1884. (Specimens) I To all whom, it may concern.-

Be it known that I, ANDREW DERROM, a

resident 01' Paterson, in the county of Passaic and State of New Jersey, have invented an Improved Composition Mastic for Covering Roofs, T elegraph-Wires, and the like, of which the following is a full, clear, and exact specifi= cation.

This invention relates to a new mixture of two peculiar natural products which are found along the northern part of South America. These are, first, a hard Venezuelan bituminous deposit, known as crude hard Venezuelan bitumen, found in Venezuela and on the north coast of South America, or other hard crude asphaltum; secondly, soft bitumen that flows by volcanic action in a lake near Maturin, Venezuela; The soft bitumen is first refined and then boiled, and the hard bitumen is then melted in the boiled soft bitumen. The best proportions are about ten parts of soft to five parts, by measure, of the hard bitumen; but good results have also been obtained by mix- I l I ing ten parts of the soft,with two parts of the hard, and two parts of the soft,with ten parts of the hard, bitumen. The mixture is peculiarly adhesive and very elastic and pliable, and furnishes an excellent ductile covering for telegraph-wires, roofs, and the like. The soft bitumen alone is not useful, because it cannot I be made hard or plastic except at very great 

